Sample carrier and sample holder

ABSTRACT

The invention relates to a composite structure of a sample carrier  20  and a sample holder  30  for use in a TEM, for example. The sample carrier is hereby separately embodied from the sample holder. Although such compositions are already known, the known compositions are very fragile constructions. The sample carrier according to the invention can be formed from a strip of metal, and is a simple and cheap element. Using resilient force, it clamps onto or into the sample holder. The portion of the sample holder to which the sample carrier couples also has a simple form. The sample carrier can couple to the sample holder in vacuum using a coupling tool.

The invention relates to a co-operative composite structure of a samplecarrier and sample holder arranged so that a sample can be attachedthereto, which sample carrier and sample holder are arranged to be usedin a vacuum, comprising:

-   -   A first portion embodied as a sample holder with an extremity        that is arranged to be removably attachable to the sample        carrier, and;    -   A second portion embodied as a sample carrier, arranged so that        the sample can be attached thereto or thereon, which sample        carrier is also arranged to be removably attachable to the        sample holder;    -   Whereby the removable attachment functionality is realized with        the aid of clamping by a resilient element.

The invention also relates to a method of removably attaching andseparating such a co-operative composite structure.

Such a co-operative composite structure is known from Japanese patentdocument No. JP-A-H04-206333.

Such a co-operative composite structure is used, for example, ininspecting samples with the aid of a Transmission Electron Microscope(TEM), e.g. in biological or materials science research laboratories andin the pharmaceutical industry. Such a co-operative composite structureis also used, for example, in inspecting samples such as are extractedfrom semiconductors in the semiconductor industry.

In a TEM, for example, a parallel, high-energy beam of electrons with anenergy of, for example, 300 keV is shot at the sample. As a result ofinteraction between the electrons and the sample, electrons in the beamwill, for example, be deflected, loose energy or be absorbed, which canyield information about the sample. By arranging the electron beam toimpinge in the correct manner upon, for example, a fluorescent screenand/or a CCD camera, the information can be rendered visible.

The sample can also be irradiated by a focused beam, which beam is movedacross the sample. In this mode of operation of a TEM, the so-calledScanning Transmission Electron Microscopy mode (STEM mode),position-dependent information in the form of secondary particles, suchas secondary electrons and X-rays, is produced.

In the case of inspection with a TEM, a very high resolution can beachieved. Nowadays, a resolution of better than 0.1 nm is achievable. Inaddition, it is, for example, possible to obtain position-dependentinformation about the material constitution using X-ray analysis in aTEM.

As a result of the strong interaction between electrons and material, asample for a TEM should be very thin. If a sample is too thick, no orvirtually no electrons will pass through it. A suitable thickness for asample is less than, for example, 100 nm, and preferably less than 50nm.

TEM samples with a thickness of, for example, less than 100 nm are ofthemselves too fragile to be manipulated with a manipulator, and areusually mounted on a thin round foil with a diameter of 3.05 mm and athickness of, for example, less than 20 μm. The central portion of sucha foil is embodied as a gauze, whereby the electrons can move throughthe sample and through the holes in the gauze without being absorbed bythe material of the foil. This foil—the so-called grid—is subsequentlymounted in a hollow of a sample holder, which sample holder in turn isattached to a manipulator of the TEM. Such grids, made from variousmaterials and with various sizes of the meshes of the gauze and athickness of, for example, about 15 μm, are commercially available.

So as to be able to properly study a sample, it is not only necessary toposition the electron beam with respect to the sample, but it is oftenalso necessary to be able to inspect the sample at an angle. To thisend, not only does the manipulator move the sample holder—and, thereby,also the sample—in an x-y plane perpendicular to the electron beam, butit can also turn, for example, about the longitudinal axis of the sampleholder, in the x-y plane (the so-called α-tilt). The sample holder canalso be arranged in such a way that the extremity hereof, on which thesample is mounted, can also cant in a canting direction located in thex-y plane and perpendicular to the α-tilt—the so-called β-tilt.Moreover, one ensures in this manner that the middle of the sample staysat the same position, the so-called Eucentric position.

Because the space that is available between the pole pieces of thelenses of a TEM is very limited, this all has to fit into a very smallspace. One must realize here that the extremity of the sample holder inits un-canted state must fit within a cylinder with a diameter of, forexample, 5 mm.

In view of the resolution of, for example, less than 0.1 nm that can beachieved with a TEM, sample holders must also be mechanically verystable. It should also be noted that the extremity of a sample holder,together with the facilities that are necessary to make the cantingmotion possible, has to operate in vacuum, which places restrictions on,for example, the use of lubricants and plastics. Finally, it should benoted that there are sample holders that must be able to operate at verylow temperatures (e.g. the temperature of liquid helium) or very hightemperatures (e.g. 500° C.).

Sample holders are therefore often expensive and fragile components,with a very specific form.

So as to give a sample a thickness of, for example, 50 nm, the samplewill have to be thinned before it is studied in a TEM. This can, forexample, be done by shooting an ion beam at it in vacuum in anotherapparatus, whereby so-called ion milling occurs.

In a method that is often used, the sample is first mounted on a TEMgrid, after which the sample holder is introduced into an apparatus thatcomprises both a column of a Scanning Electron Microscope (SEM) and acolumn of a Focused Ion Beam (FIB). Such apparatus are commerciallyavailable, e.g. the DualBeam™ apparatus of the firm FEI Company inHillsboro, USA.

In such a DualBeam™ apparatus, the sample is first localized on the gridwith the aid of the SEM column, after which it is subsequently thinnedto the desired thickness using the FIB column, while the progress of thethinning operation is monitored with the aid of the SEM column.

It should be clear that, in performing this method, it is preferable ifthe very fragile grid, which is only about ten micrometers thick, onlyhas to be mounted on a sample holder once. Demounting the grid from asample holder, and subsequent re-mounting on another sample holder,leads to a significant loss of time, and there is an additionalsignificant risk that the grid, and the sample mounted thereon, will bedamaged. However, the sample holder and manipulator of, for example, aDualBeam™ apparatus have a different form to those of a TEM, inter aliabecause the motional degrees of freedom in a DualBeam™ apparatus aremuch greater.

It should be noted that it may be desirable to study the sample inapparatus other than a TEM, such as an X-ray analyzer, an Augerspectroscope, or a SIMS apparatus (Secondary Ion Mass Spectrometer).These apparatus usually have different sample holders and manipulatorsto those that are used in a TEM. However, it is also preferable in thiscase if the fragile grid only has to be mounted once. In general, a TEMwill place the greatest restrictions on the sample holder as regardssize.

The co-operative composite structure of sample holder and sample carrierknown from JP-A-H04-206333 aims to improve the interchangeability ofsamples. To this end, the sample is first mounted on a grid, after whichthe grid is mounted on a sample carrier in the form of a thin plate,which sample carrier can be attached to the sample holder. This plate issufficiently robust to be easily exchangeable between differentapparatus.

The known co-operative composite structure is schematically shown inFIG. 1. The operation of the known co-operative composite structure willnow first be discussed.

The grid 14, to which a sample can be attached, is laid within a hollow13 of the sample carrier 12, and subsequently fixed in place using apressing screw 15. The sample carrier 12 exhibits an extremity 12 a witha hole 16. The sample holder 11 has an extremity 11 a with a pin 17thereon. The sample holder also exhibits a resilient element 19 thatcloses across the extremity 11 a. By opening the resilient element 19against the resilient force, the extremity 12 a of the sample carrier 12can be laid upon the extremity 11 a of the sample holder 11, in such amanner that the hole 16 falls over the pin 17 in the sample holder. Bynow releasing the resilient element 19, this will close across theextremity 12 a of the sample carrier 12, as a result of which the samplecarrier 12 will be clamped between the resilient element 19 and theextremity 11 a of the sample holder 11.

The known co-operative composite structure is a complex arrangement withmany components. One must remember in this context that the maximalwidth and cross-section of both the sample carrier and the sample holdermay only be a few millimeters, so as to have enough room in the TEM tobe able to cant, for example. The screw with which the grid is mountedon the sample carrier is a fragile component, which is difficult tohandle during assembly. The screw thread in the sample carrier is alsofragile, and careless treatment will easily cause the screw, the samplecarrier or both to be damaged. Manufacture of the screw and the screwthread requires precision mechanical techniques, which leads to highcosts.

The axle of the turning mechanism via which the resilient element closesitself is small, and therefore fragile. The spring that yields theresilient force is very small, and should be enclosed in a small space.Consequently, jamming of the resilient element can easily occur, as aresult of which the resilient element no longer easily closes, anddamage to the spring, the resilient element or the axle easily occurs.It should be noted in this regard that, for use in vacuum, no or only afew lubricants can be employed.

As a result of the abovementioned fragility and the increase in frictionin vacuum, the known co-operative composite structure is not suitablefor mounting the sample carrier onto the sample holder in vacuum. Theknown co-operative composite structure therefore does not lend itself tothe automatic exchange of samples in vacuum.

The invention aims to provide a co-operative composite structure ofsample carrier and sample holder that has a simpler and more robustcomposition than the known co-operative composite structure.

To this end, the co-operative composite structure according to theinvention is characterized in that the resilient element is part of thesample holder.

The invention is based upon the insight that the method whereby thesample is first mounted on a grid (as has historically evolved in thecourse of many tens of years), this grid is subsequently mounted on thesample carrier, and the sample carrier is then coupled to the sampleholder, is unnecessarily complicated. In addition, the construction thatresults herefrom, whereby a conventional TEM grid has to be fixed inplace on a sample carrier with screw connections, is unnecessarilycomplicated and fragile.

By mounting the sample directly onto the sample carrier, the difficultoperation of mounting the fragile grid on the sample carrier becomesunnecessary.

The invention is also based on the insight that it is possible to give asimple form to the sample carrier and the extremity of the sampleholder, in such a manner that the sample carrier has a resilient portionthat can be clamped onto or into the sample carrier via clamping. Thiscan, for example, be achieved by embodying the sample carrier to have abent lip of resilient material at one extremity, which bent lip fallsinto a hollow in the sample holder, for example. In this manner, theextremity of the sample holder does not have any mutually movablediscrete components. The sample carrier also does not have any mutuallymovable discrete components. As a result of the lack of such discretecomponents, the construction is much more robust.

In an embodiment of the co-operative composite structure according tothe invention, the sample carrier is formed as a single entity.

By forming the sample carrier to be a single entity, the sample carrierbecomes more robust.

An attendant advantage is that this leads to a cheaper sample carrierthan the sample carrier of the known JP patent document.

In another embodiment of the co-operative composite structure accordingto the invention, the sample carrier is arranged to be able to deform insuch a manner that attachment or disconnection of the sample carrierto/from the sample holder can proceed without, or almost without, force.

By reducing the force with which the sample carrier clamps onto or intothe sample holder during attachment or disconnection, i.e. reducing theforce at those moments that the sample holder and sample carrier are incontact with one another and have to move with respect to one another,wear of, for example, the sample holder will reduce. It is hereby alsopossible to perform attachment or disconnection in vacuum in such amanner that the lack of lubricating means will not lead to undesiredjamming (vacuum welding) of components.

This way of attaching or disconnecting can be realized by, for example,depressing the resilient portion of the sample carrier when mounting thesample carrier on the sample holder, so that the sample carrier can beapplied to the sample holder without, or almost without, force.

In yet another embodiment of the co-operative composite structureaccording to the invention, the sample carrier and sample holder areformed in such a way that, when the sample carrier is attached to thesample holder, at least five degrees of freedom are reproducibly fixed.

By reproducibly fixing degrees of freedom, the position of a givenlocation on the sample carrier with respect to the sample holder isbetter defined. This is of advantage when a sample carrier, on which asample with a given region of interest is located, is fixed to thesample holder. This is because only a small portion of the samplecarrier need be searched when at least five degrees of freedom—e.g. twotranslation vectors and three angular dependencies—between the samplecarrier and the sample holder are fixed.

It should be noted that, even if not all degrees of freedom arereproducibly fixed, once the sample carrier is affixed to the sampleholder, the friction that occurs as a result of the resilient force withwhich the two portions are clamped to one another will prevent mutualmovement of the portions.

In a further embodiment of the co-operative composite structureaccording to the invention, the number of degrees of freedom isreproducibly fixed by using a combination of a contact plane between thetwo portions, a ridge in one of the portions and a groove in the otherportion.

Using this combination, a rotational freedom (in the longitudinaldirection of the ridge), and a translational freedom (transverse to theridge) are, in principle, reproducibly fixed. Together with therequirement of contact at a contact plane between sample carrier andsample holder (as a result of the clamping), five degrees of freedom arethus reproducibly fixed: all rotational freedoms and two of the threetranslational freedoms.

In another, further embodiment of the co-operative composite structureaccording to the invention, the number of degrees of freedom isreproducibly fixed by using a contact plane between the two portions, aspherical protrusion in one of the portions and a hole in the otherportion.

Using the combination of a sphere and a hole, two translational freedomsare, in principle, fixed. Together with the requirement of contact at acontact plane between sample carrier and sample holder (as a result ofthe clamping), five degrees of freedom are thus reproducibly fixed: alltranslational freedoms and two of the three rotational freedoms.

In yet another embodiment of the co-operative composite structureaccording to the invention, the sample carrier is arranged so that aconventional TEM grid can be mounted thereon.

So as to obtain compatibility with sample holders from other apparatus,which generally use the conventional TEM grids, it is desirable toembody the sample carrier in such a way that a conventional TEM grid canbe mounted hereon. This can, for example, be achieved by equipping thesample carrier with lips, which can be folded across the grid so as toattach the grid to the sample carrier.

In another embodiment of the co-operative composite structure accordingto the invention, the sample carrier is arranged in such a manner that aconventional TEM grid mounted thereon can be demounted.

After a conventional TEM grid has been mounted on the sample carrieraccording to the invention, if this grid is also to be re-used inapparatus that cannot deal with the sample carrier according to theinvention, then it is desirable to be able to remove the TEM grid again.This can, for example, be achieved by using an appropriate punch to cutloose from the sample carrier lips that are folded across the sample soas to attach the grid to the sample carrier, so that the grid isseparated from the sample carrier.

In another embodiment of the co-operative composite structure accordingto the invention, the sample carrier is equipped to attach samples at anedge portion. This embodiment is especially attractive when attachingsamples such as are extracted from semiconductor wafers in thesemiconductor industry. Such samples are cut out of a semiconductorwafer with the aid of an ion ray. By holding the sample carrier againstthe sample and administering a gas in the vicinity of the sample,material originating from the gas can be deposited onto the sample andthe sample carrier using a focused electron beam or a focused ion beam(Electron Beam Induced Deposition (EBID) and Ion Beam Induced Deposition(IBID)). As a result of this deposition, the sample is adhered to thesample carrier. This adhesion can best be performed at a (protruding)edge portion of the sample carrier, because the sample carrier can thenbe maneuvered to the sample in the best manner.

In yet another embodiment of the co-operative composite structureaccording to the invention, the sample carrier contains a metal.

The sample carrier should be made from an electrically conductingmaterial, so as to avoid charging of the sample and the sample carrieras a result of bombardment with charged particles. Such charging canotherwise cause unwanted influencing of, for example, the electron beamor secondary electrons. The sample carrier should also be made fromelastic material. By using a metal, one can easily satisfy theserequirements.

It should be noted that the whole sample carrier does not have to bemade from the same material, but that, for example, the portion on whichthe sample can be mounted can, for example, be made from an electricallyconductive plastic, or can consist of a thin layer of carbon.

In yet another embodiment of the co-operative composite structureaccording to the invention, the sample carrier contains Mo, Cu, Be, Cand/or Si.

The use of sample carriers with a beryllium or carbon extremity, or atleast an extremity that is coated with these materials, is known per se,and occurs in those situations involving the study of the X-rayradiation that is emitted as a result of bombarding a sample withelectrons. Beryllium and carbon generate relatively little X-rayradiation, because they are materials with few protons in the nucleus.Beryllium and carbon are also good electrically conducting materials, sothat charging is prevented.

The use of molybdenum is attractive when, for example, studyingsemiconductor samples, because these usually do not comprise anymolybdenum of themselves. All radiation detected from molybdenum cantherefore be neglected and can be attributed to molybdenum present inthe sample carrier. Molybdenum is also an elastic and good electricallyconducting material, so that charging is prevented.

The use of a copper alloy is attractive because such alloys are oftenelastic and good electrically conducting materials, which can beprocessed easily.

The use of silicon is predominantly attractive when studying samplessuch as are extracted from semiconductor wafers in the semiconductorindustry, using X-ray analysis, for example. This is because thesesamples consist to a large extent of silicon, whereas the structuresthat are to be studied consist, for example, of metals. The presence ofsilicon can then be ignored during the X-ray analysis.

In yet another embodiment of the co-operative composite structureaccording to the invention, the sample carrier demonstrates a perforatedportion on which the sample can be mounted.

The perforated portion makes it possible to attach samples in a mannerthat is known from the use of conventional TEM grids.

In a further embodiment of the co-operative composite structureaccording to the invention, the perforated portion has a thickness of atmost 50 μm.

By embodying the sample carrier at the location of the perforatedportion to be thin, e.g. 50 μm or less, the perforated portion, for agiven separation of its bars, will also demonstrate good transparencywhen the sample carrier is canted, so that a sample mounted thereon canbe studied at a canting angle.

In another embodiment of the co-operative composite structure accordingto the invention, the sample carrier is attached to the sample holderwith a coupling tool. The use of a coupling tool offers greatadvantages, in view of the tiny size of the sample carrier.

In another embodiment of the co-operative composite structure accordingto the invention, the coupling tool is an automatic coupling tool.

An automatic coupling tool makes it possible to automate processes, andit also makes it possible to attach the sample carrier to a sampleholder in vacuum. The latter is of particular importance in so-calledcryo applications, where a sample carrier that has already beenpre-cooled has to be attached to a sample holder at cryogenictemperatures, e.g. temperatures in the vicinity of that of liquidnitrogen or of liquid helium.

In another embodiment of the co-operative composite structure accordingto the invention, the sample holder is arranged to co-operate with apositioning unit.

Co-operation with a positioning unit, such as a goniometer, makes itpossible, for example, to position the co-operative composite structurewith respect to an ion beam, so as to thin the sample, or with respectto a electron beam, so as to study the sample.

In yet another embodiment of the co-operative composite structureaccording to the invention, the sample carrier is provided with anidentification code.

The presence of an identification code makes it easy to distinguishbetween different sample carriers with different samples, though thesemight otherwise appear to be identical.

In an aspect of the method according to the invention, the samplecarrier couples to the sample holder, which method comprises thefollowing steps:

-   -   Picking up the sample carrier using a tool;    -   Deforming the sample carrier in such a manner as to greatly        reduce the force that, during insertion, is exerted by one        portion on the other portion as a result of the resilient force        of the resilient element;    -   Mutually moving the sample holder and the sample carrier towards        one another;    -   Coupling the sample carrier to the sample holder, and;    -   Releasing the sample carrier from the tool.

In another method according to the invention, the sample carrierdecouples from the sample holder, which method comprises the followingsteps:

-   -   Applying a tool to the sample carrier, which sample carrier is        connected to the sample holder;    -   Deforming the sample carrier in such a manner as to greatly        reduce the force that, during disconnection, is exerted by one        portion on the other portion as a result of the resilient force        of the resilient element;    -   Disconnecting the sample carrier from the sample holder;    -   Mutually moving the sample carrier and the sample holder away        from one another, and;    -   Releasing the sample carrier from the tool.

In a further method according to the invention, coupling of the samplecarrier to the sample holder or decoupling of the sample carrier fromthe sample holder occurs in vacuum.

In a yet further method according to the invention, the vacuum is partof a Transmission Electron Microscope (TEM), a Scanning TransmissionElectron Microscopy (STEM), a Scanning Electron Microscope (SEM), anElectron Microprobe Analyzer (EPMA), a Focused Ion Beam apparatus (FIB),an Auger analyzer, a Secondary Ion Mass Spectrometer (SIMS), a ScanningProbe Microscope (SPM), an X-ray analyzer, a sputter coater, a plasmacleaner or an evaporative deposition unit.

In another method according to the invention, the sample is applied tothe sample carrier by at least partially coating the sample carrier witha liquid or powdery material.

In a further method according to the invention, before attaching thesample to the sample carrier, at least a portion of the sample carrieris provided with a sticky layer, after which the sample is adhered tothe sticky layer.

The invention will now be elucidated on the basis of figures, wherebythe same reference numerals indicate corresponding structures.

To this end:

FIG. 2 schematically shows the sample carrier according to theinvention;

FIG. 3 schematically shows the extremity of the sample carrier accordingto the invention;

FIG. 4 schematically shows the sample carrier and the sample holderaccording to the invention, which are coupled to one another;

FIG. 5 schematically shows a coupling tool, with therein the samplecarrier according to the invention;

FIG. 6 schematically shows a coupling tool, the sample carrier and thesample holder according to the invention;

FIG. 7 schematically shows an embodiment of the sample carrier accordingto the invention, which is suited to carrying a conventional TEM grid;

FIG. 8 schematically shows a sample holder according to the invention,which is suited to attaching samples at edge portions, and;

FIG. 9 schematically shows a sample carrier according to the invention,which is suited to having a liquid or powdery sample stuck thereto.

FIG. 2 schematically shows in a front view (FIG. 2A) and in top view(FIG. 2B) a sample carrier according to the invention.

The sample carrier 20, formed from a thin strip 21 of, for example,molybdenum with a width 28, is folded at fold 22 and demonstrates aridge 23. An extremity 24 of this strip 21 is provided with a gauze-likeportion 25. This extremity 24 can have the same thickness as the rest ofthe strip 21, but can also be thinner, as here depicted.

Beside the extremity 24, an identification region 26 is present on thestrip, where an identification code has been applied.

In non-depressed state, the sample carrier has a height 27.

By now moving points X and X′, for example, toward one another, thisheight 27 will decrease, and a resilient force will arise with which thesample carrier can clamp into the sample holder.

It should be noted that the designation “side view”, “top view” and“front view” are defined with respect to the electron beam in a TEM;usually, this beam is incident from above upon the gauze-like portion ofthe sample carrier, such as a conventional TEM grid or a sample carrieraccording to the invention.

FIG. 3 schematically shows the extremity of the sample holder accordingto the invention in side (FIG. 3A), top view (FIG. 3B) and in a frontview (FIG. 3C).

The extremity of the sample holder has a cavity 31 with a width 32 and aheight 33. The width 32 is somewhat larger than the width of the samplecarrier 20, and the height 33 is somewhat smaller than the height 27 ofthe sample carrier in non-depressed state. There are also two hollows 35present, with a width 36. As will be elucidated in FIG. 5, these hollows35 with width 36 make it possible to use a coupling tool, with a widthat the tip somewhat smaller than the width 36, for the purpose ofcoupling and decoupling the sample carrier 20 to/from the sample holder30. Furthermore, the sample holder 30 demonstrates a contact plane 37.

FIG. 4 schematically shows the sample carrier and the sample holderaccording to the invention, which are coupled to one another.

Sample carrier 20, with a sample 1 thereon, is slid into sample holder30. The sample carrier lies on contact plane 37 of the sample holder 30,and ridge 23 of the sample carrier falls into one of the hollows 35 ofthe sample holder. Because the height 33 of the sample holder is alittle smaller than the height 27 of the sample carrier in itsnon-depressed state, a clamping of the sample carrier 20 in the sampleholder 30 will occur.

As a result of laying the sample carrier 20 on the contact plane 37, andbecause ridge 23 falls into one of the hollows 35, five of the sixdegrees of freedom with which the sample carrier 20 can be attached intothe sample holder 30 are reproducibly fixed; only the position of thesample carrier with respect to the sample holder in the longitudinaldirection of the ridge 23 is not fixed.

It should be noted that, although the position of the sample carrier 20with respect to the sample holder 30 in the longitudinal direction ofthe ridge 23 is not fixed, this can not lead to mutual movement, becausethe friction occurring as a result of the clamping prevents suchmovement.

It should be noted that embodiments are also possible whereby the ridgeis made in the sample holder 30 and the groove is made in the samplecarrier 20.

FIG. 5 schematically shows a coupling tool and a sample carrieraccording to the invention.

The coupling tool 50 consists of a resilient body 51 with two jaws 53and 54, and a stop 52. The sample carrier 20 with sample 1 can be slidinto the coupling tool, as shown.

Normally, the coupling tool will be somewhat open, in such a manner thatthe distance 55 between the jaws 53 and 54 of the coupling tool isgreater than the height 27 of the sample carrier 20 in non-depressedstate. By now pushing the jaws 53 and 54 toward one another, the samplecarrier located in the coupling tool is depressed. The stop 52 limitsthe maximal amount by which the coupling tool is depressed. The maximalamount of depression is such that the height 27 is limited by the stop52 at a height that is a little smaller than the height 33 of the sampleholder 30. In this manner, it is possible to depress the sample carrier20 in such a way that it can be inserted into the sample holder 30without touching the latter.

The jaws 53 and 54 are narrowed, so that these will fit within thehollow 35 of the sample holder 30. To this end, the width of the jaws 53and 54 is a little smaller than the width 36 of the hollows 35 in thesample holder 30.

It should be noted that embodiments of the coupling tool are alsopossible whereby the movement of the jaws is realized using, forexample, an electric motor. Such a coupling tool, which may be part of aTEM, for example, can then be embodied as an automatic coupling tool,whereby coupling and decoupling occur under the control of a controlunit.

It is also possible with such an automatic coupling tool to performcoupling or decoupling of the sample carrier in vacuum.

FIG. 6 schematically shows a coupling tool, the sample carrier and thesample holder according to the invention.

In this figure, it can be seen how the jaws 53 and 54 of the couplingtool 50 fall within the hollow 35 of the sample holder 30.

FIG. 7 schematically shows an embodiment of the sample carrier accordingto the invention, which is suited to carrying a conventional TEM grid.

In this embodiment, the sample carrier 20 demonstrates four lips 70 thatcan be folded down. By placing a conventional TEM grid 71, with a sample1 mounted thereon, upon the sample carrier, and by subsequently foldingdown the lips 70, the grid 71 is attached to the sample carrier 20.

By cutting off the lips 70, e.g. with a punch that cuts through thesample carrier 20 along the contour 72, the grid 71 with the sample 1located thereupon is freed once again, and the grid 71 can, for example,be attached once again to traditional TEM sample holders.

FIG. 8 schematically shows a sample carrier according to the invention,which is suited to attaching samples at edge portions.

As a result of the presence of several protruding portions 80, thisembodiment lends itself to the adhesion to the sample carrier of samplessuch as semiconductor samples 2, e.g. by adhesion using ion depositionor using a sticky substance.

FIG. 9 schematically shows a sample carrier according to the invention,which is suited to having a liquid or powdery sample stuck thereto.

In, for example, the petrochemical industry, there is a need to studymaterials that are present in solution with a volatile liquid. Bydipping the extremity 90 of the sample carrier into the solution andsubsequently allowing the volatile liquid to evaporate, the materialthat is to be studied is left behind on the sample carrier. By suitablychoosing the volatile liquid, adhesion of the material to be studiedonto the sample carrier will thereby occur.

It is also possible to first coat the extremity 90 of the sample carrierwith a sticky layer, after which the material to be studied, e.g. as apowdery material, can adhere to the sample carrier.

It should be noted that this embodiment shows a sample carrier that isnot transparent to electrons, so that the sample therefore cannot beirradiated through by a particle beam. In general, however, the presenceof a gauze-like portion is not a requirement for many study techniques.

Study techniques that do not require a gauze-like portion are, forexample, Auger spectroscopy, SEM and X-ray analysis.

It should also be noted that it is possible to make a sample carrierthat is similar to the sample carrier of FIG. 9 but that is transparentto electrons, e.g. by embodying the extremity 90 as a thin film ofcarbon or, for example, silicon nitride, with or without localreinforcement using a gauze.

Although the preceding text describes a combination of a sample carrierand a sample holder whereby the sample carrier clamps within a hollow ofthe sample holder, the inventor is aware that there are also embodimentswhereby the sample carrier clamps around the sample holder.

Protection is also sought for this and for other embodiments and methodssuch as can be derived by the skilled artisan herefrom.

1. A co-operative composite structure of a sample carrier and sampleholder arranged so that a sample can be attached thereto, which samplecarrier and sample holder are arranged to be used in a vacuum,comprising: A first portion embodied as a sample holder with anextremity that is arranged to be removably attachable to the samplecarrier; A second portion embodied as a sample carrier, arranged so thatthe sample can be attached thereto or thereon, which sample carrier isalso arranged to be removably attachable to the sample holder; Wherebythe removable attachment functionality is realized with the aid ofclamping by a resilient element; and The resilient element forms part ofthe sample holder.
 2. A co-operative composite structure according toclaim 1, whereby the sample carrier is formed as a single entity.
 3. Aco-operative composite structure according to claim 1, whereby thesample carrier is arranged to be able to deform in such a manner thatattachment or disconnection of the sample carrier to/from the sampleholder can proceed without, or almost without, force.
 4. A co-operativecomposite structure according to claim 1, whereby the sample carrier andthe sample holder are formed in such a way that, when they are attachedto one another, at least five degrees of freedom are reproducibly fixed.5. A co-operative composite structure according to claim 4, whereby fivedegrees of freedom are reproducibly fixed by using a combination of acontact plane between the two portions, a ridge in one portion and agroove in the other portion.
 6. A co-operative composite structureaccording to claim 4, whereby five degrees of freedom are reproduciblyfixed by using a combination of a contact plane between the twoportions, a spherical protrusion in one portion and a hole in the otherportion.
 7. A co-operative composite structure according to claim 1,whereby the sample carrier is arranged so that a conventional TEM gridcan be mounted thereon.
 8. A co-operative composite structure accordingto claim 7, whereby the sample carrier is arranged in such a manner thata conventional TEM grid mounted thereon can be demounted.
 9. Aco-operative composite structure according to claim 1, whereby thesample carrier is equipped to attach samples at an edge portion.
 10. Aco-operative composite structure according to claim 1, whereby thesample carrier contains a metal.
 11. A co-operative composite structureaccording to claim 1, whereby the sample carrier contains Mo, Cu, Be, Cand/or Si.
 12. A co-operative composite structure according to claim 1,whereby the sample carrier demonstrates a perforated portion, on whichportion a sample can be mounted.
 13. A co-operative composite structureaccording to claim 12, whereby the perforated portion has a thickness ofat most 50 μm.
 14. A co-operative composite structure according to claim1, whereby the sample carrier is attached to the sample holder with acoupling tool.
 15. A co-operative composite structure according to claim14, whereby the coupling tool is an automatic coupling tool.
 16. Aco-operative composite structure according to claim 1, whereby thesample holder is arranged to co-operate with a positioning unit.
 17. Aco-operative composite structure according to claim 1, whereby thesample carrier is provided with an identification code.
 18. A samplecarrier for use in a co-operative composite structure according toclaim
 1. 19. A sample holder for use in a co-operative compositestructure claim
 1. 20. A method for coupling a co-operative compositestructure of a sample carrier and a sample holder, which methodcomprises the following steps: Picking up the sample carrier using atool; Deforming the sample carrier in such a manner as to greatly reducethe force that, during insertion, is exerted by the two portions uponone another; Mutually moving the sample holder and the sample carriertowards one another; Coupling the sample carrier to the sample holder;and Releasing the sample carrier from the tool.
 21. A method ofdisconnecting a co-operative composite structure of a mutually connectedsample carrier and sample holder, which method comprises the followingsteps: Applying a tool to the sample carrier, which sample carrier isconnected to the sample holder; Deforming the sample carrier in such amanner as to greatly reduce the force that, during disconnection, isexerted by the two portions upon one another; Disconnecting the samplecarrier from the sample holder; Mutually moving the sample carrier andthe sample holder away from one another; and Releasing the samplecarrier from the tool.
 22. A method according to claim 20, whereby themethod is performed in a vacuum.
 23. A method according to claim 22,whereby the vacuum is part of a TEM or a STEM or a SEM or a FIB or anAuger analyzer or a SPM or an X-ray analyzer or a sputter coater or aplasma cleaner or an evaporative deposition unit or a SIMS.
 24. A methodaccording to claim 20, whereby coupling the sample carrier to the sampleholder comprises applying the sample to the sample carrier by at leastpartially coating the sample carrier with a liquid or powdery material.25. A method according to claim 20 further comprising, before couplingthe sample to the sample carrier, at least a portion of the samplecarrier is provided with a sticky layer, after which the sample isadhered to the sticky layer.
 26. A method according to claim 21, wherebythe method is performed in a vacuum.
 27. A co-operative compositestructure of a sample carrier and sample holder arranged so that asample can be attached thereto, which sample carrier and sample holderare arranged to be used in a vacuum, comprising: A first portionembodied as a sample holder with an extremity that is arranged to beremovably attachable to the sample carrier; A second portion embodied asa sample carrier, arranged so that the sample can be attached thereto orthereon, which sample carrier is formed as a single entity and alsoarranged to be removably attachable to the sample holder; Whereby thesample carrier is arranged to be able to deform in such a manner thatattachment or disconnection of the sample carrier to/from the sampleholder can proceed without, or almost without, force; Whereby the samplecarrier and the sample holder are formed in such a way that, when theyare attached to one another, at least five degrees of freedom arereproducibly fixed; and Whereby the removable attachment functionalityis realized with the aid of clamping by a resilient element and theresilient element forms part of the sample holder.
 28. A co-operativecomposite structure according to claim 27, whereby five degrees offreedom are reproducibly fixed by using a combination of a contact planebetween the two portions, a ridge in one portion and a groove in theother portion.
 29. A co-operative composite structure according to claim27, whereby five degrees of freedom are reproducibly fixed by using acombination of a contact plane between the two portions, a sphericalprotrusion in one portion and a hole in the other portion.